Conditional unmarshalling of processInstance (via MarshallingConfiguration) causes errors when unmarshalling

See this commit: https://github.com/droolsjbpm/drools/commit/e1e913de731b6011f1d2f4c290e327b60b388a63.

What I'm seeing in my test results is that this change makes it complicated to unmarshall the process.

The problem is that this makes marshalling of a processInstance dependent on booleans set at runtime (marshallProcessInstances and marshallWorkItems). But we can't know what those booleans were set to if we then try to unmarshall the process later... etc.

The fix for this bug ensures that the anything written by the OutputMarshaller, is also read in by the InputMarshaller.